CVEs / CVE-2015-3246
CVE-2015-3246: Red Hat Libuser Race Condition Vulnerability
- Known exploited in the CISA KEV catalog since 26 Aug 2026
- high 7.2 CVSS 2.0 (NVD)
- EPSS 8.5% chance of exploitation in the next 30 days, higher than 95% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Red Hat libuser contains a race condition vulnerability that allows authenticated local users to corrupt the /etc/passwd file to cause a denial of service or privilege escalation.
Description
libuser before 0.56.13-8 and 0.60 before 0.60-7, as used in the userhelper program in the usermode package, directly modifies /etc/passwd, which allows local users to cause a denial of service (inconsistent file state) by causing an error during the modification. NOTE: this issue can be combined with CVE-2015-3245 to gain privileges.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| n/a n/a | n/a | — |
Exploitation
| In CISA KEV since | 26 Aug 2026 |
|---|---|
| Due date for US federal agencies | 9 Sep 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. |
Severity
| CVSS 2.0 | 7.2 highAV:L/AC:L/Au:N/C:C/I:C/A:CScored by NVD |
|---|---|
| Weakness | CWE-264, CWE-367 |
References
- CVE-2015-3246 on NVD
- CVE-2015-3246 in the CISA KEV catalog
- https://access.redhat.com/articles/1537873 (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk (cited by CISA)
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk (cited by CISA)
- CVE-2015-3246 on OSV
- http://lists.fedoraproject.org/pipermail/package-announce/2015-August/163044.html Broken Link
- http://lists.fedoraproject.org/pipermail/package-announce/2015-July/162947.html Broken Link
- http://lists.opensuse.org/opensuse-security-announce/2015-08/msg00000.html Mailing List, Third Party Advisory
- http://rhn.redhat.com/errata/RHSA-2015-1482.html Vendor Advisory
- http://rhn.redhat.com/errata/RHSA-2015-1483.html Vendor Advisory
- http://www.securityfocus.com/bid/76022 Third Party Advisory
- http://www.securitytracker.com/id/1033040 Third Party Advisory
- https://access.redhat.com/articles/1537873 Mitigation, Vendor Advisory
- https://www.exploit-db.com/exploits/44633/ Third Party Advisory, VDB Entry
- https://www.qualys.com/2015/07/23/cve-2015-3245-cve-2015-3246/cve-2015-3245-cve-2015-3246.txt Exploit
- https://blog.talosintelligence.com/uat-10147-chinese-speaking-adversary-integrates-agentic-ai-into-post-compromise-operations/ Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2015-3246 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.